[PATCH] nvmet: Add support for reservations.

[Omri Mann]

A list of registrants, protected by RCU, is kept for each namespace and a
reference for the reservation type and holder.
Each I/O operation is checked for reservation conflict.

For every change in the reservation status that warrants it, a log page
entry is generated for each controller that should receive it, and an
Asynchronous event is sent to all relevant controllers that have not
been sent one since the last time they have read the reservation log page.

Reservation status structures definitions were copied from nvme-cli.

This patch does not include support for persistency across power failures.

On Mon, Sep 4, 2017 at 5:26 PM, Johannes Thumshirn <jthumshirn at suse.de> wrote:
> Hi Omri,
>
> a bit more information (a.k.a. a commit message) would be helpful to review
> your patch. Also I do not see how you intent to make persistant reservation
> survive across reboots.
>
> Thanks,
>         Johannes
>
> --
> Johannes Thumshirn                                          Storage
> jthumshirn at suse.de                                +49 911 74053 689
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